Connecting Dc Power Cables To The Acx1000 Or Acx1100 Router - Juniper ACX1000 Hardware Manual

Connecting DC Power Cables to the ACX1000 or ACX1100 Router

To connect DC power to the router, you need the following tools:
• Phillips (+) screwdriver, number 2
• ESD grounding wrist strap
• M3 screws and flat washers
• DC power source cables, minimum 14 AWG or as required by local code (not provided)
• Ring lugs, Molex 190700067 or equivalent (not provided)
The DC power supply has four terminals on the front panel, covered by a clear plastic cover.
WARNING: You must ground the router before connecting the DC power cables.
To connect the power cables:
1. Switch off the dedicated customer site circuit breakers. Ensure that the voltage across the DC
power source cable leads is 0 V and that there is no chance that the cable leads might become
active during installation.
2. Remove the clear plastic cover protecting the terminal on the faceplate.
3. Verify that the DC power cables are correctly labeled before making connections to the power
supply. In a typical power distribution scheme where the return is connected to chassis ground at
the battery plant, you can use a multimeter to verify the resistance of the DC cables to chassis
ground:
For –48V and –60V:
a. The cable with very large resistance (indicating an open circuit) to chassis ground is the DC input
cable (–).
b. The cable with very low resistance (indicating a closed circuit) to chassis ground is the return
cable (+).
For +24V:
a. The cable with very low resistance (indicating a closed circuit) to chassis ground is the DC input
cable (–).
b. The cable with very large resistance (indicating an open circuit) to chassis ground is the return
cable (+).
4. Install heat-shrink tubing insulation around the power cables.
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